新型矿用比例方向阀动态特性及控制方法分析

Dynamic Characteristics and Control Method Analysis of a Novel Mine Proportional Directional Valve

适用于液压支架的比例方向阀代替现有的开关型方向阀,是液压支架智能化的重要组成部分。提出了一款适用于液压支架系统的比例方向阀方案,其兼有手动开关控制模式和电液比例控制模式,建立了其数学模型和仿真模型,分析了其动静态特性。研究表明:主阀进液阀芯位移与输入信号占空比呈线性反比例关系;合理设计反馈槽宽度和进液阀芯面积比可以提高阀芯的响应速度;当仅有液压反馈时,进液阀芯位移仍受控于输入信号,避免了因传感器失效对控制系统造成的灾难性事故的发生;通过增加电反馈与原有液压反馈构成双反馈控制的方式,大幅提高了阀的响应速度、线性度、滞环等特性。

It is an important part of intelligent hydraulic support that the proportional directional valve suitable for the hydraulic roof support replaces the existing on-off directional valve.This paper presents a proportional directional valve scheme suitable for the hydraulic support system.The novel proportional directional valve has both manual on-off control mode and electro-hydraulic proportional control mode,its mathematical model and simulation model are established,and its dynamic and static characteristics are analyzed.The research shows that the inlet valve spool displacement of the main valve is linearly inversely proportional to the duty cycle of the input signal.The response speed of the valve can be improved by reasonably designing the width of the feedback groove and the area ratio of the inlet valve spool.When there is only hydraulic feedback,the displacement of the inlet valve spool is still controlled by the input signal,so the catastrophic accidents caused by sensor failure to the control system are avoided.A double feedback control mode composed of the electric feedback and the hydraulic feedback can greatly improve the response speed,linearity and hysteresis of the valve.